Исследование гидродинамики и теплообмена при неизотермическом течении углеводородной вязкой среды в трубопроводе, проложенном в районе многолетнемерзлых грунтов

В процессе исследования проводились расчеты изменений полей скорости, распределений температуры по длине трубопровода; зависимости теплового пограничного слоя от длины трубопровода. Анализировались процессы конвективного теплообмена в условиях развивающегося потока и формирования теплового и динамического пограничных слоев по длине. В результате исследования был произведен сравнительный анализ интегро-дифференциальных и точных методов моделирования динамики и теплообмена при течении углеводородных сред в трубопроводах на начальных участках в режимах вязкостно-инерционного ламинарного и турбулентного течения и теплообмена.In the course of the study, calculations were made of changes in the velocity fields and temperature distributions along the pipeline; the dependence of the thermal boundary layer on the length of the pipeline. The processes of convective heat transfer under the conditions of the developing flow and the formation of thermal and dynamic boundary layers along the length were analyzed. The study resulted in a comparative analysis of integro-differential and accurate methods for modelling the dynamics and heat transfer during the flow of hydrocarbon media in pipelines in the initial sections in the modes of viscous-inertial laminar and turbulent flow and heat transfer

The influence of bisphosphonates on human osteoblast migration and integrin aVb3/tenascin C gene expression in vitro

<p>Abstract</p> <p>Background</p> <p>Bisphosphonates are therapeutics of bone diseases, such as Paget's disease, multiple myeloma or osteoclastic metastases. As a severe side effect the bisphosphonate induced osteonecrosis of the jaw (BONJ) often requires surgical treatment and is accompanied with a disturbed wound healing.</p> <p>Therefore, the influence on adhesion and migration of human osteoblasts (hOB) after bisphosphonate therapy has been investigated by morphologic as well as gene expression methods.</p> <p>Methods</p> <p>By a scratch wound experiment, which measures the reduction of defined cell layer gap, the morphology and migration ability of hOB was evaluated. A test group of hOB, which was stimulated by zoledronate 5 × 10^-5M, and a control group of unstimulated hOB were applied. Furthermore the gene expression of integrin aVb3 and tenascin C was quantified by Real-Time rtPCR at 5data points over an experimental period of 14 days. The bisphosphonates zoledronate, ibandronate and clodronate have been compared with an unstimulated hOB control.</p> <p>Results</p> <p>After initially identical migration and adhesion characteristics, zoledronate inhibited hOB migration after 50 h of stimulation. The integrinavb3 and tenascin C gene expression was effected by bisphosphonates in a cell line dependent manner with decreased, respectively inconsistent gene expression levels over time. The non-nitrogen containing bisphosphonates clodronate led to decreased gene expression levels.</p> <p>Conclusion</p> <p>Bisphosphonates seem to inhibit hOB adhesion and migration. The integrin aVb3 and tenascin C gene expression seem to be dependent on the cell line. BONJ could be enhanced by an inhibition of osteoblast adhesion and migration. The gene expression results, however, suggest a cell line dependent effect of bisphosphonates, which could explain the interindividual differences of BONJ incidences.</p

Influence of lip closure on alveolar cleft width in patients with cleft lip and palate

<p>Abstract</p> <p>Background</p> <p>The influence of surgery on growth and stability after treatment in patients with cleft lip and palate are topics still under discussion. The aim of the present study was to investigate the influence of early lip closure on the width of the alveolar cleft using dental casts.</p> <p>Methods</p> <p>A total of 44 clefts were investigated using plaster casts, 30 unilateral and 7 bilateral clefts. All infants received a passive molding plate a few days after birth. The age at the time of closure of the lip was 2.1 month in average (range 1-6 months). Plaster casts were obtained at the following stages: shortly after birth, prior to lip closure, prior to soft palate closure. We determined the width of the alveolar cleft before lip closure and prior to soft palate closure measuring the alveolar cleft width from the most lateral point of the premaxilla/anterior segment to the most medial point of the smaller segment.</p> <p>Results</p> <p>After lip closure 15 clefts presented with a width of 0 mm, meaning that the mucosa of the segments was almost touching one another. 19 clefts showed a width of up to 2 mm and 10 clefts were still over 2 mm wide. This means a reduction of 0% in 5 clefts, of 1-50% in 6 clefts, of 51-99% in 19 clefts, and of 100% in 14 clefts.</p> <p>Conclusions</p> <p>Early lip closure reduces alveolar cleft width. In most cases our aim of a remaining cleft width of 2 mm or less can be achieved. These are promising conditions for primary alveolar bone grafting to restore the dental bony arch.</p

Loneliness and Social Isolation among Transgender and Gender Diverse People

Here, we report the prevalence of loneliness and social isolation and investigate the levels of loneliness and social isolation among transgender and gender diverse people using cross-sectional data from the HH-TPCHIGV study. Using the De Jong Gierveld tool, we assess loneliness, using the Bude and Lantermann tool, we assess perceived social isolation and using the Lubben Social Network Scale, we assess objective social isolation. The prevalence rate of loneliness was 83.3% (perceived social isolation: 77.7%; objective social isolation: 34.4%). Regressions revealed that favorable outcomes (i.e., lower loneliness levels, lower perceived social isolation, and lower objective social isolation) were consistently associated with higher school education. Beyond that, we identify an association between particularly poor health-related factors and higher loneliness and objective social isolation levels. We also report that unemployment was significantly associated with higher levels of perceived social isolation. In conclusion, we show high prevalence rates of loneliness and social isolation among transgender and gender diverse people. Additionally, important correlates (e.g., education, health-related factors, or unemployment) were identified. Such knowledge may provide help to address transgender and gender diverse people at risk for loneliness and social isolation

Frequency of probable social media addiction and correlates of problematic social networking sites use in a sample of transgender adults

Aim: Transgender people face many unique challenges. Thus, some of them report excessive use of social media. Our aim was to identify the frequency of social media addiction and to investigate the factors associated with problematic social networking sites use exclusively amongst transgender adults in times of the Covid-19 pandemic. Subjects: We used data from the “Transgender Survey” HH-TPCHIVG (n = 104 in the analytical sample). Transgender people from self-help groups were involved in gathering information about gender-affirming surgery at a German hospital were included. Specific exclusion criteria did not exist. The validated Bergen Social Media Addiction Scale served as a tool to quantify probable social media addiction. Results: In sum, 20.5 % of the transgender people are probably addicted to social media. Regressions showed that problematic social networking sites use was significantly positively associated with the presence of a migration background (β = 2.41, p < 0.05), and a higher frequency of sports activities. Conclusion: In conclusion, our study stressed the challenge of probable social media addiction among transgender people. Knowledge about the correlates of problematic social networking sites use may assist in addressing individuals at risk. The associations identified in this study could be explained, by, among other things, body dissatisfaction (especially with regard to sporting activities) or increased internet contacts (for people with a migration background). Efforts to reduce social media addiction (e.g., awareness-raising, promotion of offline activities, using role models) could prove effective in this group, pending longitudinal research

Prevalence and Determinants of Depressive and Anxiety Symptoms among Transgender People: Results of a Survey

Objectives: The aim was to investigate the prevalence of probable depression and probable anxiety and to investigate the determinants of depressive symptoms and anxiety symptoms among transgender people. Methods: In this “Transgender Survey” (n = 104) we included transgender people who had joined self-help groups to obtain and share information about the gender-affirming surgeries performed at the Division of Plastic, Reconstructive and Aesthetic Surgery at the University Medical Center Hamburg-Eppendorf. Data collection took place between April and October 2022. To measure probable depression, the patient health questionnaire-9 was used. The generalized anxiety disorder-7 was used to quantify probable anxiety. Results: The prevalence of probable depression was 33.3% and it was 29.6% for probable anxiety. Multiple linear regressions showed that both more depressive symptoms and anxiety symptoms were significantly associated with younger age (β = −0.16, p &lt; 0.01; β = −0.14, p &lt; 0.01), being unemployed (e.g., full-time employed compared to unemployment: β = −3.05, p &lt; 0.05; β = −2.69, p &lt; 0.05), worse self-rated health (β = −3.31, p &lt; 0.001; β = −1.88, p &lt; 0.05), and having at least one chronic disease (β = 3.71, p &lt; 0.01; β = 2.61, p &lt; 0.05). Conclusions: Remarkably high prevalence rates were identified among transgender people. Furthermore, risk factors of poor mental health (e.g., unemployment or younger age) were identified—which can help to address transgender people at risk for poor mental health.</jats:p